$ D = \left[\begin{array}{rr}2 & 9 \\ 6 & 3\end{array}\right]$ What is $ D^{T}$ ?
Answer: To find the transpose, swap the rows and columns. $ D^{T}$ = $\left[\begin{array}{rr}2 & 6 \\ 9 & 3\end{array}\right]$